Track construction for ground effect machines

ABSTRACT

A track for an air cushion vehicle, having a structure comprising a flexible deck which has the required surfaces for supporting and guiding the vehicle and which is suspended, by means of shackles, on cables which are supported at intervals along the track, on pylons or the like.

United States Patent [72] Inventor gancoi; L. Giraud 56 Reference Cit d aisir, rance [2] 1 App O 741,435 UNITED STATES PATENTS [22] Filed July 1, 1968 440,437 1 H1890 Phillips 14/6 [45] Patented Feb 9 1971 534,032 2/1895 Clymerm 14/6 Assignee Societe De 634,026 lO/1899 Pittman 14/6 Paris France 2,057,168 10/1936 Strauss 14/6 a company of France 3,190,235 6/1965 Bertin et a1. 104/134 [32] Priority Dec. 12, 1967 Primary Examiner-Joseph R. Leclajr [33] France Assistant Examiner.lames R. Garrett 1 131,91 Attorney-Stevens, Davis, Miller & Mosher [54] TRACK CONSTRUCTION FOR GROUND EFFECT MACHINES 4 Claims, 7 Drawing Figs.

[52] US. Cl [04/120, 1

104/23 ABSTRACT: A track for an air cushion vehicle, having a [51] Int. Cl 860v l/02, structure comprising a flexible deck which has the required 7 A g w n B6lb 13/08 surfaces for supporting and guiding the vehicle and which is [50] Field of Search 104/23, suspended, by means of shackles, on cables which are sup- 124, 120, 134, l 19; 105/ 145; 14/6 ported at intervals along the track, on pylons or the like.

PATENTED rm 9 law SHEET 1 0F 2 PATENTFU FEB 9 l9?l SHEET 2 OF 2 TRACK CONSTRUCTION FOR GROUND EFFECT MACHINES The present invention relates to a track along which hovercraft or other ground-effect machines can travel by means of cushions of pressurized fluid provided to eliminate mechanical frictional contact between the vehicle and the track. Tracks of this kind are nowadays well known and have been previously described in US. Pat. No. 3,190,235, to Bertin et al.

It is well known that the weight of a ground-effect machine is generally distributed over virtually the whole of the base area thereof by means of pressurized fluid cushions on which the vehicle is supported. The result is that the pressure due to this load over the surface along which the machine travels, is low. The lateral forces such as centrifugal force in curved sections of the track, aerodynamic forces due to gusts of wind, and so on, are absorbed by central and/or lateral guides.

Thus, it is possible to produce a track, which is suitable for this purpose although both narrow and light, by using lightweight structures, for example, hollow materials such as prestressed porous concrete with closed cells or metal box structures or beams with suitable stiffening.

In accordance with the present invention, there is provided a track for supporting ground effect machines through pressure fluid cushions formed against a bearing track surface, said surface comprising a flexible trackway resting upon cables which are suspended at points spaced along the track.

In the accompanying drawings:

FIG. 1 is a schematic longitudinal, sectional elevation illustrating the general arrangement of the various components of one embodiment of track according to the invention;

FIGS. 2A and 2B are two transverse half-sections on a larger scale, taken respectively on the lines [IA-IIA and IIB-IIB of FIG. 1, and showing additionally the arrangement of the cushions of pressurized fluid associated with a groundeffect machine moving along the track;

FIG. 3 is a detailed view, on a larger scale, of the track showing the attachment of a seal, this view being a section taken on the line III-III of FIG. 4;

FIG. 3A schematically illustrates an extreme position which the seal may occupy;

FIG. 4 is a sectional view taken on the line IV-IV of FIG. 3; and

FIG. 5 is a detailed view, in transverse section, of an altemative embodiment of a structural detail.

In FIGS. 1 and 2, the head 1 of a T-shaped pylon can be seen, also a central upright 2 which supports the guide air cushions 13 of a machine M, these guide air cushions being confined by skirts 14. The said upright 2 may be made of a lightweight material, reinforced or otherwise, such as cellular concrete or any other material having equivalent mechanical properties, or may take the form of metal box structures or beams suitably stiffened and advantageously of cavity design.

Rigid track strips 3a which may be made of the same material are likewise mounted on cantilever head I. In addition, the central upright 2 has flanges forming track strips 3!). Crosspieces 4 are provided to maintain constant spacing between these various elements.

Lateral skirts 5, advantageously of flexible design, which are attached to the framework of the machine M and which contain supporting air cushions 6, are located opposite the said track strips 3a and 3b.

The gap between these track strips 3a3b is spanned by flexible trackways 9 against which the fluid cushions 6 bear and which are carried by cables 8 clamped at [6 to props 7 fast with the pylon heads 1 and at 22 therebetween to studs 9a which stay these trackways 9.

The stationary track strips 3a, 3b and the flexible trackways 9 extending between them are separated by clearances which are straddled by seals 10 better illustrated on FIGS. 3, 3A and 4.

The seals 10 are formed of thin sheet metal, impermeable canvas or a sheet of plastics material. They may contain holes II suitably located so that with the trackway 9 in the rest posi tion, rainwater is discharged.

A guide 12 guides the flexible trackway 9 relatively to the track strips 3a, 3b and forms spaced transverse partitions across the gap between the trackway 9 and the adjoining track strips 3a and 3b. The seals 10 are designed to undergo deformations due to diflerences in level occurring between the said track strips 3a, 3b.

I claim:

1. A ground-effect transit system comprising an elevated track with a cushion bearing track surface and a fluid cushion machine (M) movable along said track .with the interposition of a fluid cushion (6) formed against the track surface, wherein the improvement comprises a flexible trackway (9) incorporated in said cushion bearing track surface over a major portion of the area thereof and made of a fluidtight material adapted to flex yieldingly upon cushion pressure being exerted thereon during passage of said machine, longitudinally extending cables (8) for yieldably supporting said flexible trackway, and means (1-7-16) for suspending said cables at longitudinally spaced points thereof.

2. Transit system as claimed in claim I. wherein said cushion bearing track surface further incorporates rigid and substantially undeformable track strips (30, 3b) extending on both sides of said flexible trackway (9) with clearances therebetween, whereby said track surface is hybrid, being part flexible and part rigid. I

3. Transit system as claimed in claim 2, further comprising seals (10, 18) straddling said clearances.

4. Transit system as claimed in claim 2, wherein said fluid cushion machine comprises longitudinally extending cushion seals (5) positioned opposite said rigid track strips (30, 3b). 

1. A ground-effect transit system comprising an elevated track with a cushion bearing track surface and a fluid cushion machine (M) movable along said track with the interposition of a fluid cushion (6) formed against the track surface, wherein the improvement comprises a flexible trackway (9) incorporated in said cushion bearing track surface over a major portion of the area thereof and made of a fluidtight material adapted to flex yieldingly upon cushion pressure being exerted thereon during passage of said machine, longitudinally extending cables (8) for yieldably supporting said flexible trackway, and means (1-7-16) for suspending said cables at longitudinally spaced points thereof.
 2. Transit system as claimed in claim 1, wherein said cushion bearing track surface further incorporates rigid and substantially undeformable track strips (3a, 3b) extending on both sides of said flexible trackway (9) with clearances therebetween, whereby said track surface is hybrid, being part flexible and part rigid.
 3. Transit system as claimed in claim 2, further comprising seals (10, 18) straddling said clearances.
 4. Transit system as claimed in claim 2, wherein said fluid cushion machine comprises longitudinally extending cushion seals (5) positioned opposite said rigid track strips (3a, 3b). 